Abstract: An oscillator wafer-level-package structure is provided, comprising a bottom layer, an oscillator crystal and a capping layer. The bottom layer includes an upper plane, the capping layer includes a lower plane, and the oscillator crystal is disposed between the bottom layer and the capping layer and includes at least one cavity. An upper seal ring and a lower seal ring are respectively surrounding the oscillator crystal such that the oscillator crystal is sealed in between the capping layer and the bottom layer by employing the upper and lower seal rings. In addition, a diffusion barrier is further disposed in the upper seal ring and in the lower seal ring for avoiding interface diffusion. Moreover, the present invention adopts the same material for fabricating the capping layer, the oscillator crystal and the bottom layer to achieve an optimal thermal stress result when realizing the packaging structure.

Abstract: An oscillator wafer-level-package structure is provided, comprising a bottom layer, an oscillator crystal and a capping layer. The bottom layer includes an upper plane, the capping layer includes a lower plane, and the oscillator crystal is disposed between the bottom layer and the capping layer and includes at least one cavity. An upper seal ring and a lower seal ring are respectively surrounding the oscillator crystal such that the oscillator crystal is sealed in between the capping layer and the bottom layer by employing the upper and lower seal rings. In addition, a diffusion barrier is further disposed in the upper seal ring and in the lower seal ring for avoiding interface diffusion. Moreover, the present invention adopts the same material for fabricating the capping layer, the oscillator crystal and the bottom layer to achieve an optimal thermal stress result when realizing the packaging structure.

Abstract: Disclosed is a process and apparatus for transferring heat from a heat source at a first temperature to a heat sink at a second higher temperature in a phase change of a heat transfer fluid. The heat transfer fluid is subjected to a pressure variation which changes the temperature at which the phase change takes place.